Google APIs are application programming interfaces developed by Google which allow communication with Google Services and their integration to other services.
websites using the $ symbol on their website - meaning it may accept payment in this currency used in Israel.
Content Security Policy is best used as defense-in-depth, to reduce the harm caused by content injection attacks.
The http-equiv attribute provides an HTTP header for the information/value of the content attribute. The http-equiv attribute can be used to simulate an HTTP response header.